(2) Cause the source(s) to be shielded when an entrance door is opened; and

(3) Prevent the source(s) from being exposed following an interlock interruption
until all treatment room entrance doors are closed and the source(s) on-off
control is reset at the console.

(c) A licensee shall require any individual entering the treatment room to
assure, through the use of appropriate radiation monitors, that radiation levels
have returned to ambient levels.

(d) Except for low-dose remote afterloader units, a licensee shall construct
or equip each treatment room with viewing and intercom systems to permit continuous
observation of the patient or the human research subject from the treatment
console during irradiation.

(e) For licensed activities where sources are placed within the patient's or
human research subject's body, a licensee shall only conduct treatments which
allow for expeditious removal of a decoupled or jammed source.

(f) In addition to the requirements specified in paragraphs (a) through (e)
of this section, a licensee shall--

(i) An authorized medical physicist and either an authorized user or a physician,
under the supervision of an authorized user, who has been trained in the operation
and emergency response for the unit to be physically present during the initiation
of all patient treatments involving the unit; and

(ii) An authorized medical physicist and either an authorized user or an individual,
under the supervision of an authorized user, who has been trained to remove
the source applicator(s) in the event of an emergency involving the unit, to
be immediately available during continuation of all patient treatments involving
the unit.

(2) For high dose-rate remote afterloader units, require--

(i) An authorized user and an authorized medical physicist to be physically
present during the initiation of all patient treatments involving the unit;
and

(ii) An authorized medical physicist and either an authorized user or a physician,
under the supervision of an authorized user, who has been trained in the operation
and emergency response for the unit, to be physically present during continuation
of all patient treatments involving the unit.

(3) For gamma stereotactic radiosurgery units, require an authorized user and
an authorized medical physicist to be physically present throughout all patient
treatments involving the unit.

(4) Notify the Radiation Safety Officer, or his/her designee, and an authorized
user as soon as possible if the patient or human research subject has a medical
emergency or dies.

(g) A licensee shall have applicable emergency response equipment available
near each treatment room to respond to a source--